JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD B.Tech II Year ELECTRICAL ENGINEERING Previous Question Paper (March - 2021 - R13)

When a conductor carrying a current I is placed in a uniform magnetic field with flux density B, it experiences a mechanical force F. This force arises from the interaction between the magnetic field and the moving charges within the conductor.

The magnitude of the force is given by the expression:

Where:

• F is the force in Newtons (N).
• B is the magnetic flux density in Tesla (T).
• I is the current in Amperes (A).
• L is the length of the conductor in meters (m).
• θ is the angle between the direction of the current and the magnetic field lines.

The direction of this force is determined by Fleming's Left-Hand Rule. By stretching the thumb, forefinger, and middle finger of the left hand mutually perpendicular to each other, if the forefinger points in the direction of the magnetic field and the middle finger points in the direction of the current, the thumb indicates the direction of the force exerted on the conductor.

Since the circuit diagram was not provided in the prompt, the general procedure to determine branch currents is as follows:

1. Identify all nodes and loops within the circuit.
2. Apply Kirchhoff's Current Law (KCL) at independent nodes, which states that the algebraic sum of currents entering a node is zero.
3. Apply Kirchhoff's Voltage Law (KVL) to each independent loop, ensuring the algebraic sum of voltages around any closed path is zero.
4. If the circuit is complex, utilize Nodal Analysis by assigning a reference node (ground) and writing KCL equations for the remaining node voltages.
5. Solve the resulting system of simultaneous linear equations for the unknown currents or voltages.
6. Once node voltages are determined, calculate individual branch currents using Ohm's Law (I = V/R) for each resistive element.